Electrical heat producing element



June 9, 1931. OSTRAK ELECTRICAL HEAT PRODUCING ELEMENT Filed Jan. 18, 1929 Patented June 9, 1931 PATENT: OFFICE .rossrn osrnax, or s'r. LOUIS, mssoum ELEGIRIGAL HEAT PRODUCING ELEMENT Application filed January 18, 1929. Serial No. 338,847.

included each a resistance conductor which,

when the unit was in'operation, emitted heat.

These resistance conductors were usually in the form of single wires of relatively small diameter, and hence the heat producing areas thereof were quite limited. The main purpose of the present invention is to increase the effective heat producin areas of the heat producing elements, and. t is purpose is accomplished b associating with the resistance conductors p at -like members of substantial area to which heat is transmitted b the said resistance conductors. Because 0 this arrangement the heat roduced by the resistance conductors is distributed over a substantially greater area than heretofore, whereby theefiectiveness of the heat producing elements is increased.

Fig. 1 illustrates a fragmentary view of a-casm or housing constructed in accordance with my invention.

Figs. 2, 3, 4, and 5 illustrate the principle of my invention applied to heat distributing elements of various shapes.

Fig. 6 is an enlarged fragmentary perspective of theheat producing unit, several ofwhich are shown in association with the end walls of the casing shown in Fig. 1.

Fi 7 is an' enlar ed fragmentary perspectlve illustratingt e arrangement shown in Fig. 4. Fig. 8 is an enlar ed fragmentary perspective illustrating t 1e arrangement shown in Fig. 5.

In the drawings, wherein is illustrated one embodiment merely of the invention, and referring particularly to Fig. 1 thereof,

instead of being confined to the area of the A designates a casing or housing, which may, for instance, be a heating or drying element of some'sort, the portion of said casing or housing which is illustrated including a side wall B and the opposite end walls 0 thereof. The side wall B of the casin or housing A illustrated in Fig. 1 is provi ed with a plurality of recesses 1 spaced longitudinally of said side wall, each of said recesses being substantially U-shaped and comprising a pair of spaced side walls 2 which are joined together by a curvedbottom wall 3.

Arranged within each of the recesses 1 is a high resistance electric wire 4, said wire 4 being extended longitudinally of said recess. .5 The wall B of the casing A may be formed of'a metal which is a conductor of electricty, and when this is so I associate with each hi h resistance wire an electrical insulating e ement 5. The insulatin elements 5 serve to prevent the passage of ectrical energy from the various resistance wires 4 to the wall B of the casing or housing, but these insulating elements are not heat insulators and hence do not' prevent the passage of heat from the resistance wires 4 to thewall B. It will be noted that the insulatin elements 5 are of substantially the same s ape as the recesses 1; that is to say, each insulating element is substantially U-shaped and the wall portion so thereof is interposed between the outer surface of the associated resistance wire and the inner face of the recess.

Because of the arran ment of the resistance wires within the -shaped recesses 1, it is plain that a greater portion of outer surface of each resistance wire is in close proximity to the wall of the U-shaped recess 1 in which said resistance wire is positioned,

hence most of the heat emitted from the re- 96 sistance wire will be transniitted to the walls of the recess. The walls of the recesses 1 are associated with wall portions B, which. are

of substantial area and to which heat transmitted to the walls of the recesses by the re- 05 sistance wires passes, hence said heat is distributed over a substantially wide area instead of being confined to the relativel small area of the resistance wires as hereto ore.

The end walls 0 of the casing or housing 100 A are provided with a plurality of straps 6, which are rigidly attac ed thereto as shown in Figs. 1 and 6. When viewed in lan or horizontal section, the ortion of eac strap 6 intermediate of the-si e edges thereof which are secured to the associated wall is spaced a art from the face of the wall C to which t e strap is attached, to provide a space in which a high resistance wire 4 and an insum lating element 5 arepositioned in the manner in which the resistance wires and insulators are associated in the U-shaped recess 1 formed in the side wall B of the casing or housing A. The resistance wires and insu- 1 lators associated with the strap 6 extend longitudinally of the spaces within said straps, and because the greater portion of the outer surface of each of said resistance wires is arranged in close proximity to the walls of the g9 straps 6 and to the end walls G of the casing or housing A, most of the heat emitted from said resistance wires will be transmitted to the straps and end wall 0, whereby said heat will be distributed over substantial area.

In Figs. 2, 3, 4; and 5 my improved heat producing arrangement is shown in association with heat distributing elements of various shapes. However, in each of these forms of the invention the resistance wires and so the insulators associated therewith are positioned within U-sha ed recesses. I

In Fig. 2 the heat distributing element comprises a circular wall B, which .joins the walls of the U-shaped recesses being extended in- 9! wardly with respect to said circular wall B. In Fig. 3 a heat distributing element B is illustrated with respect to which U-shaped recesses 1 extend outwardly.

The heat distributing element shown in Fig. 4 comprises a substantially diamondshaped figure, the wall rtions B of said element which connect t e walls of the U- shaped recess 1 being straight instead of curved, as in Figs. 2 and 3.

cross-section comprises a simp e elongated hereunto afiix my si In Fig. 5 the heat distributin element in I claim:

A heat producing unit comprising a hi h resistance electric conductor, a heat distn uting element associated with said high resistance conductor, said heat distributing element being of greater area than said high resistance conductor and being provided with a substantially U-shaped recess in which said high resistance conductor is positioned in a manner to cause wall portions of the recess to be in close proximity to a plurality of sides of said high resistance conductor, and a substantially U-shaped electric insulating element interposed between said high resistance conductor and portions of the wall of said recess, said recess bein of a depth which is substantially greater t an the correspondin dimension of the electric conductor, w ereby the heat distributing area of the walls of said recess is increased.

In testimony that I claim the foregoing I ature.

. OSEPH OSTRAK.

loop B and the resistance wires and 1nsulators are positioned in the U-shaped recesses 1' rovided at the opposite ends of said 1001).

n all of the forms of the invention illustrated it will be noted that the wall ortions of the heat distributors to which eat is transmitted by the resistance wires are arranged in close proximity to said resistance wires on a plurality of sides thereof. Because of this arrangement it is lain that most of the heat will pass directly ance wires to the walls of the heat distributors whereby very little heat emitted from said resistance wires will be lost.

When the wall portions of the heat distributing elements are formed of material which is a non-conductor of electricity, the instilithtors 5 may, of course, be dispensed wi om the resist 

